Multi-battery charging station which selectively connects battery sub-modules to a common power bus for charging

Abstract

Battery sub-modules are selecting to electrically connect to a common power bus, including by: determining if a discharge-related fault indication for a given battery sub-module indicates that the given battery sub-module is in a discharge-related fault condition. If so, the given battery sub-module is excluded from the selected battery sub-modules such that said given battery sub-module is electrically disconnected from the common power bus. The selected battery sub-modules are configured so that the selected battery sub-modules are electrically connected to the common power bus; the selected battery sub-modules that are electrically connected to the common power bus are charged.

What is claimed is: 
     
       1. A system, comprising:
 a power bus; 
 a plurality of battery sub-modules connected to the power bus; 
 a charger interface coupled to the plurality of battery sub-modules; 
 a charger coupled to the charger interface and configured to:
 charge one or more of the plurality of battery sub-modules; 
 receive, via the charger interface, a plurality of metrics associated with the plurality of battery sub-modules, wherein the plurality of metrics include a first metric associated with a first battery sub-module; 
 minimize a charging time of the first battery sub-module based on the first metric via the charger interface. 
 
 
     
     
       2. The system of  claim 1 , wherein charger is further configured to:
 select a first set of battery sub-modules among the plurality of battery sub-modules based on the metrics associated with the one or more battery sub-modules, wherein the first set of battery sub-modules are determined to collectively charge faster than remaining battery sub-modules; and 
 charge the first set of battery sub-modules. 
 
     
     
       3. The system of  claim 1 , wherein the plurality of metrics are dynamic values that are received periodically from the plurality of battery sub-modules with a frequency of once every one or more charging cycles. 
     
     
       4. The system of  claim 1 , wherein the plurality of metrics are received periodically from the plurality of battery sub-modules when a predetermined event occurs. 
     
     
       5. The system of  claim 1 , further comprising:
 a battery management system coupled to each one of the plurality of battery sub-modules, wherein a first battery management system coupled to the first battery sub-module is configured to estimate or measure the first metric for the first battery sub-module. 
 
     
     
       6. The system of  claim 1 , further comprising:
 a battery management system coupled to each one of the plurality of battery sub-modules, wherein a given battery management system coupled to a given battery sub-module is configured to detect that the given battery sub-module is in a fault state, and inform the charger that the given battery sub-module is in the fault state. 
 
     
     
       7. The system of  claim 6 , wherein charger is further configured to:
 disconnect the given battery sub-module from the power bus. 
 
     
     
       8. The system of  claim 1 , wherein the plurality of metrics include one or more of a temperature, a state of charge, a maximum cell voltage, and a minimum current associated with each battery sub-module among the plurality of battery sub-modules. 
     
     
       9. The system of  claim 1 , wherein the plurality of metrics include a set of metrics associated with each battery sub-module, wherein a charging state for a given battery sub-module is based on a totality of the set of metrics associated with the given battery sub-module. 
     
     
       10. The system of  claim 1 , wherein the charger is further configured to:
 charge the plurality of battery sub-modules in a constant current state mode where the charger maintains a charging current value at a predetermined constant charging current; 
 determine that a maximum cell voltage for a given battery sub-module among the plurality of battery sub-modules reached a threshold value; and 
 switch from the constant current state mode to a constant cell voltage state mode where the charger sets the charging current value to a value to maintain the maximum cell voltage at a predetermined value. 
 
     
     
       11. The system of  claim 1 , wherein the charger is further configured to:
 stop charging the plurality of battery sub-modules when a charging current value of the charger drops to a predetermined value. 
 
     
     
       12. The system of  claim 1 , wherein the charger is further configured to:
 stop charging the plurality of battery sub-modules when a charging time exceeds a predetermined threshold. 
 
     
     
       13. The system of  claim 1 , wherein the charger is further configured to:
 determine a minimum battery sub-module current, wherein the minimum battery sub-module current is lowest among battery sub-module currents associated with the plurality of battery sub-modules; 
 charge the plurality of battery sub-modules at a first charging current set based on at least the minimum battery sub-module current; 
 obtain a global maximum cell voltage, wherein the global maximum cell voltage is highest among maximum cell voltages associated with the plurality of battery sub-modules; and 
 charge the plurality of battery sub-modules at a second charging current set based on at least the global maximum cell voltage until the global maximum cell voltage exceeds a threshold value. 
 
     
     
       14. The system of  claim 1 , further comprising:
 a heating and cooling system associated with one or more battery sub-modules, 
 wherein the charger is further configured to:
 receive a temperature of a given battery sub-module among the plurality of battery sub-modules; 
 determine that the temperature of the given battery sub-module is outside a predetermined range; and 
 activate the heating and cooling system via the charger interface to heat or cool the given battery sub-module; and 
 start charging the given battery sub-module when the temperature of the given battery sub-module is within the predetermined range. 
 
 
     
     
       15. The system of  claim 14 , wherein the heating and cooling system includes one or more heating coils associated with one or more battery sub-modules. 
     
     
       16. The system of  claim 1 , wherein the charger is further configured to:
 determine a given battery sub-module with a state of charge that is at a target maximum cell voltage; and 
 discharge the given battery sub-module. 
 
     
     
       17. A system, comprising:
 a power bus; 
 a plurality of battery sub-modules connected to the power bus; 
 a charger interface coupled to the plurality of battery sub-modules; 
 a charger coupled to the charger interface and configured to:
 determine a minimum battery sub-module current, wherein the minimum battery sub-module current is lowest among battery sub-module currents associated with the plurality of battery sub-modules; 
 charge the plurality of battery sub-modules at a first charging current set based on at least the minimum battery sub-module current; 
 obtain a global maximum cell voltage, wherein the global maximum cell voltage is highest among maximum cell voltages associated with the plurality of battery sub-modules; and 
 charge the plurality of battery sub-modules at a second charging current set based on at least the global maximum cell voltage until the global maximum cell voltage exceeds a threshold value. 
 
 
     
     
       18. The system of  claim 17 , wherein the charger is further configured to:
 stop charging the plurality of battery sub-modules when a charging current value of the charger drops to a predetermined value or when a charging time exceeds a predetermined threshold. 
 
     
     
       19. A system, comprising:
 a power bus; 
 a plurality of battery sub-modules connected to the power bus; 
 a charger interface coupled to the plurality of battery sub-modules; 
 a charger coupled to the charger interface and configured to:
 charge the plurality of battery sub-modules in a constant current state mode where the charger maintains a charging current value at a predetermined constant charging current; 
 determine that a maximum cell voltage for a given battery sub-module among the plurality of battery sub-modules reached a threshold value; and 
 switch from the constant current state mode to a constant cell voltage state mode where the charger sets the charging current value to a value to maintain the maximum cell voltage at a predetermined value. 
 
 
     
     
       20. The system of  claim 19 , wherein the charger is further configured to: stop charging the plurality of battery sub-modules when a charging current value of the charger drops to a predetermined value or when a charging time exceeds a predetermined threshold.